"enhanced", higher contrast color palette on heatmap about flamescope

[brendangregg]

It would be great to have an "Enhance" button that switched to a palette like this, based on count:

• 0: white
• 1-2: shades of blue (light->dark).
• 3-max: a red scale (pink->red?)

The aim is to highlight single-threaded activity, which will either have a count of 1 (eg, 49 Hertz sampling on a 50 row heatmap) or 2 (99 Hertz sampling on a 50 row heatmap). Hence making 1 & 2 blue, and the rest shades of red.

Here is an example. This is application startup, which includes many single-threaded stages. Since they have low counts in the columns, they are almost white in the default profile.

Imagine an "Enhance" button that then switched to the low-count highlighting palette:

That looks ok (the blue goes beyond a 1-2 count in this mock up, which it shouldn't). I'd resist adding more colors to this (think weather radar maps) since it can become visually ugly. Keep it simple. Blue, then a red scale.

This should be easy to do. See the colorScale() function in the heat map.

[ceeaspb]

We also get feint colors; I wanted to explore the single color.

[spiermar]

@brendangregg assuming this is closed.

[brendangregg]

@ceeaspb that's a pretty interesting profile. How does it look with the new "Enhance Colors" button? Maybe so interesting it deserves a blog post. :)

[ceeaspb]

@brendangregg sorry combination of holiday and been busy - I wasn't sure at first but yes it looks great with the enhanced palette! And yes I need to work on my blog writing skills :)
The handful of really intense cpu activity pixels was perf itself, which I should probably ask about on perf-users.